Despite my vow that I'd just play one game (which turned into "just one more," then "just one more," etc.) I found myself playing Katamari Damacy for almost three hours yesterday while I tried to reach the eternal stage for the moon. Today, I discovered a level beyond the moon, however.
Once you finish the game, go to the marker for the end credits. While the credits scroll, you can roll your katamari over the earth, picking up the countries.
It's hard to stay oriented because the earth doesn't turn on a fixed axis and will rotate in any direction you roll. It's helpful to know something about geography since you'll have to pick up the smaller countries first, and as the camera slowly pans back, it gets harder and harder to tell what you're doing.
I managed to pick up 179 countries, including some pretty big ones like the U.S., Canada, China, and Antarctica, but the king told me I was still "almost there."